TECHNICAL MANUAL OPERATOR'S, ORGANIZATIONAL, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL FOR

Transcription

1 TECHNICAL MANUAL OPERATOR'S, ORGANIZATIONAL, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL FOR SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)1 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)2 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)3 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)4 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)5 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)6 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)7 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)8 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)9 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)10 (NSN ) AND SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)12 (CONSOLE REMOTE EQUIPMENT) (NUS 7640) HEADQUARTERS, DEPARTMENT OF THE ARMY JUNE 1976

2 Technical Manual No /1 } TM /1 HEADQUARTERS DEPARTMENT OF THE ARMY Washington, D.C., 11 June 1976 OPERATOR'S, ORGANIZATIONAL, DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL FOR SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)1 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)2 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)3 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)4 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)5 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)6 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)7 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)8 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)9 (NSN ) SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)10 (NSN ) AND SWITCHING SET, COMMUNICATIONS AN/MSQ-74(V)12 (CONSOLE REMOTE EQUIPMENT) (NUS 7640) REPORTING OF ERRORS You can help improve this manual by calling attention to errors and by recommending improvements and stating your reasons for the recommendations. Your letter or DA Form 2028 (Recommended Changes to Publications and Blank Forms) should be mailed direct to the Commander, US Army Electronics Command, ATTN: DRSEL-MA-Q, Fort Monmouth, New Jersey iii

3 TABLE OF CONTENTS CHAPTER 1. PART ONE INTRODUCTION AND DESCRIPTION Para. Page Section I. Section II. Section III. CHAPTER 2. Section I. Section II. Section III. General Scope of manual Purpose and use Description and leading particulars General description Logic equipment Audio equipment FST modem equipment Matrix equipment Maintenance equipment Power supply equipment Technical characteristics Main line trunks Tributary links CRE power requirements INSTALLATION General Scope of chapter Equipment location, preliminary preparation, and interconnection Equipment layout Preliminary preparation Equipment interconnection Inspection, application of power, checkout and adjustment Visual inspection Ancillary equipment Remote equipment turn-on Programming adjustment and checkout Disconnecting equipment Packaging and preparation iv

4 TABLE OF CONTENTS (cont) CHAPTER 3. PART ONE (cont) FUNCTIONING OF EQUIPMENT Para. Page Section I. Introduction Scope of chapter System tie-in Message formats Overall block diagram description Section II. Audio equipment General Block diagram discussion Section III. Connection matrix General Block diagram discussion Section IV. FST modem equipment General Detailed description Section V. Digital signaling equipment Overall description Detailed block diagram descriptions Section VI. Power distribution Ac power distribution Dc power distribution Section VII. Distribution frame Description Section VIII. Maintenance equipment Fixed maintenance equipment Mobile maintenance equipment cabinet v

5 TABLE OF CONTENTS (cont) CHAPTER 4. Section I. Section II. Section III. PART ONE (cont) Para. Page MAINTENANCE Preventive maintenance General Daily routines Quarterly routines Semi-annual routines Annual routines Corrective maintenance General Logic and flow diagrams Maintenance controls and indicators Use of patch fields Use of character generator Use of printer Troubleshooting Adjustments General Power supplies Controlled oscillator cards FST modem keyer PART TWO CHAPTER 5. DIAGRAMS Content of chapter PART THREE APPENDIX I. MNEMONICS Description of mnemonics... A1-1 A1-1 Mnemonics glossary... A1-2 A1-1 vi

6 TABLE OF CONTENTS (cont) APPENDIX II. APPENDIX III. PART THREE (cont) Para. Page CONSOLE REMOTE EQUIPMENT TEST PROCEDURE CRE DIFFERENCE DATA CRE van configurations.... A3-1 A3-1 Purpose of difference data appendix... A3-2 A3-1 Use of difference data appendix... A3-3 A3-1 vii

7 TABLE OF CONTENTS TM /1 PART FOUR, MODULES Page No. Transmit conference amplifier NUS 7568, Card Receive conference amplifier NUS 7569, Card Dual flip-flop NUS NAND gates NUS 7571, Card 069 and NUS 8078, Card Diode cluster NUS 7572, Card 117, diode resistor network NUS 8108, Card 648; execute circuit NUS 8109, Card Single lamp driver NUS 7574, Card Controlled oscillator NUS 7576, Card Dual relay driver NUS 7577, Card way junction network NUS 7587, Card Matrix module NUS 7639G1 48 Level Adjust NUS 7665, Card Relay module NUS Relay module NUS 7737G1 61B Relay panel NUS seven input NAND gate NUS 7826, Card One second pulse sensing device NUS 7861, Card Power amplifier NUS 7862, Card Component card NUS 7916G1, G2, and G3, Card Clock driver NUS 7918, Card cycle slave/standby oscillator NUS 7961, Card two input NAND gate NUS 8077, Card Variable time pulse sensing device NUS 8103, Card Oscillator detector NUS 8104, Card Unit A low-pass filter NUS 8110, Card Holding coil driver NUS 8128, Card Ac NOR gate NUS 8311, Card Frequency shift tone keyer B Frequency shift tone converter B Carrier failure alarm A Carrier detector B G1 and G2 149 Low pass filter unit viii

8 TABLE OF CONTENTS TM /1 PART FIVE Section Page I. GENERAL INFORMATION 1-1 Introduction General Description General Configuration Operating Specifications Primary Power Requirements General Physical Characteristics II. INSTALLATION 2-1 Introduction Primary Power Connections Load Cable Connections Remote Sense Connections Remote Alarm Connections III. THEORY OF OPERATION 3-1 Introduction General System Operation Main Power Transformers Three-Phase Bridge Rectifier Circuit Input Filter Section Series Regulators Current Multiplier Section DC Error Amplifier Differential Comparator Amplifier Precision Voltage Reference Output Voltage Sampling Overvoltage Protection Circuit Circuit Breaker Protection Auxiliary Power Supply Power Supply Connections Load Current and Voltage Metering Failure Alarm System Forced Air Cooling System ix

9 TABLE OF CONTENTS (cont) TM /1 PART FIVE Section Page IV. OPERATION 4-1 Introduction Location of Operator Controls AC Circuit Breaker Sequence of Operation DC Circuit Breaker Sequence of Operation Output Voltage Adjustment Overvoltage Adjustment Preliminary Adjustments and Tests Overvoltage Adjustment Test Output Voltage Adjustment Test V. MAINTENANCE 5-1 Introduction Preventive Maintenance Routine Maintenance Requirements Fan Motor Capacitors Heat Sink Assemblies Test Procedure Removal and Replacement of Access Panels Removal and Replacement of Regulator Drawers and Fan Drawers Removal and Replacement of Printed Circuit Boards Removal and Replacement of Heat Sink Assemblies Removal and Replacement of Regulator Transistors Removal and Replacement of Receifier Elements (Stud- Mounted Semiconductor Devices) Removal and Replacement of Filter Elements Power Inductor Capacitor Removal and Replacement of Switches and Circuit Breakers Push Switches (DC Breaker By-Pass) Rotary Selection Switches Circuit Breakers Removal and Replacement of Fan Motor Removal and Replacement of Fuses Removal and Replacement of Meter Panel Removal and Replacement of Voltmeters and Ammeters x

10 Section TABLE OF CONTENTS (cont) PART FIVE Page TM /1 V. MAINTENANCE (Continued) 5-16 Removal and Replacement of Alarm Panel Removal and Replacement of Alarm Panel Indicator Lights Removal and Replacement of Control Chassis Removal and Replacement of Ammeter Shunts Removal and Replacement of Main Power Transformer 5-22 VI. Vll. TROUBLE SHOOTING 6-1 Introduction Test Equipment Required Basic Failure Analysis Unit Unit Duplexed Output Failure Localization of Failure Verification of Failure Set-Up Procedure Regulation, Ripple Overvoltage Relay Trouble Shooting instructions Repair Procedure Operational Tests Alarm Panel Test Overload Test Overvoltage Adjustment Test Output Voltage Adjustment Test SCHEMATICS 7-1 Introduction xi

11 LIST OF ILLUSTRATIONS PART ONE Figure No. Title 1-1 Console remote equipment van 1-2 Typical logic card 1-3 Typical logic cabinet, front view 1-4 Typical logic cabinet, rear view 1-5 Remote command receive cabinet, unit Typical tributary control cabinet, unit 5, 6, or Trunk matrix control cabinet, unit Select matrix control cabinet, unit Audio cabinet, unit 11, front view 1-10 Audio cabinet, unit 11, rear view 1-11 FST modem cabinet, unit 12, front view 1-12 FST modem cabinet, unit 12, rear view 1-13 Typical modem module 1-14 Matrix cabinet, unit 13, front view 1-15 Matrix cabinet, unit 13, rear view 1-16 Maintenance test fixed cabinet, unit Maintenance test fixed cabinet, unit 10, panel open 1-18 Maintenance test mobile cabinet, unit Dc duplexed power system, units 23 and Fire extinguisher mounting 2-2 Air conditioners, inside operating controls 2-3 CRE digital address pinboard programming panels 3-1 Character bit codes 3-2 Supervisory command message format 3-3 Supervisory command messages recognized by CRE 3-4 Ready command message format 3-5 CRE message formats and time relationships 3-6 CRE messages, information and status characters 3-7 FST modem, supervisory and ready carrier detector circuits, functional block diagram 3-8 FST modem, supervisory and ready receive circuits, functional block diagram xii

12 LIST OF ILLUSTRATIONS (cont) PART ONE (cont) Figure No. Title 3-9 FST modem, supervisory and ready status transmit circuits, functional block diagram 3-10 RCR flow chart (11 sheets) 3-11 RCR timing circuits, timing diagram 3-12 RCR character times 3-13 TMC flow chart (35 sheets) 3-14 Timing generator waveforms 3-15 TMC control contact circuit, simplified schematic diagram 3-16 Matrix relays and associated relay drivers, simplified schematic diagrams 3-17 SMC flow chart (29 sheets) 3-18 Timing circuit, output signal waveform 3-19 RTC flow chart (8 sheets) 3-20 RTC timing signal relationships 3-21 RTG and RTS flow chart (12 sheets) 3-22 High error alarm counter, detailed block diagram 3-23 Van ac power distribution, block diagram 3-24 Van dc power distribution, block diagram 3-25 Power fault summary circuits, simplified block diagram 3-26 Printer buffer circuit, simplified block diagram 3-27 System character generator, message formats 4-1 Mainline conference amplifiers, test setups 4-2 Logic diagram symbols (18 sheets) 4-3 Logic diagram symbols identification scheme 4-4 Typical facilities table 4-5 Inter- and intra-sheet signal referencing 4-6 Flow diagram symbols (2 sheets) 4-7 Fixed maintenance equipment cabinet, circuit breaker panel controls 4-8 Fault summary and status panel, controls and indicators 4-9 Audio panel, connector jacks 4-10 Character generator, controls and indicators xiii

13 LIST OF ILLUSTRATIONS (cont) PART ONE (cont) Figure No. Title 4-11 Printer and printer supply, controls, indicators, and connector jacks 4-12 Audio cabinet, patch field 4-13 Audio cabinet, jack location 4-14 FST modem equipment, patch field 4-15 Character generator, character codes 4-16 Character generator, character positions vs FRAME SEQUENCE switch settings PART TWO 5-1 Console remote equipment, van layout (BX A) 5-2 Console remote equipment van, exterior connector panels 5-3 ET-A console system, functional block diagram 5-4 Console remote equipment, overall block diagram 5-5 Audio equipment, functional block diagram 5-6 Connection matrix, functional block diagram 5-7 FST modem, tributary service receive and transmit circuits, functional block diagram 5-8 Digital signaling equipment, overall block diagram 5-9 RCR circuits, functional block diagram 5-10 TMC circuits, functional block diagram 5-11 SMC circuits, functional block diagram 5-12 SMC control contact circuits, simplified schematic diagram 5-13 RTC circuits, functional block diagram 5-14 Typical RTG circuits, functional block diagram 5-15 Typical RTS circuits, functional block diagram 5-16 Maintenance equipment, overall block diagram 5-17 Fault summary and status circuits, functional block diagram 5-18 System character generator circuits, functional block diagram 5-19 Logic cards, internal test points 5-20 System character generator, control settings for format A 5-21 System character generator, control settings for format B xiv

14 LIST OF ILLUSTRATIONS (cont) PART TWO (cont) Figure No. Title 5-22 System character generator, control settings for format D, remote-to-local 5-23 System character generator, control settings for format D, remote-to-tributary 5-24 System character generator, control settings for format E 5-25 Power fault troubleshooting diagram (28 sheets) 5-26 Logic fault troubleshooting diagram (50 sheets) 5-27 Character generator troubleshooting diagram (2 sheets) 5-28 CRE ac power distribution diagram (F ) (3 sheets) 5-29 CRE dc power distribution diagram (F ) (2 sheets) 5-30 CRE signal cabling diagram (F ) (3 sheets) 5-31 Unit 1, distribution frame wiring list (B ) (15 sheets) 5-32 Unit 4, RCR logic diagram (F ) (15 sheets) 5-33 Unit 4, RCR power distribution schematic (F ) 5-34 Units 5, 6, 7, RTG and RTS, logic diagram (F ) (15 sheets) 5-35 Units 5, 6, 7, RTG and RTS, power distribution schematic (F ) 5-36 Unit 8, TMC and RTC logic diagram (F ) (27 sheets) 5-37 Unit 8, TMC and RTC power distribution diagram (F ) (2 sheets) 5-38 Unit 9, SMC logic diagram (F ) (15 sheets) 5-39 Unit 9, SMC power distribution schematic (F )(2 sheets) 5-40 Unit 10, RFM schematic and interconnection diagram (F ) (16 sheets) 5-41 Unit 10, audio panel schematic ( ) 5-42 Unit 10, character generator (SCG) logic diagram (F ) (13 sheets) 5-43 Unit 10, printer supply schematic (F ) 5-44 Unit 10, RFM power distribution schematic (F ) (2 sheets) 5-45 Unit 11, audio (RAC) schematic and interconnection diagram (E ) (9 sheets) xv

15 LIST OF ILLUSTRATIONS (cont) PART TWO (cont) Figure No. Title 5-46 Unit 11, audio (RAC) power distribution schematic (F ) 5-47 Unit 12, FST modem (RTY) schematic and interconnection diagram (F ) (3 sheets) 5-48 Unit 12, mainline terminal panel schematic (D ) 5-49 Unit 12, tributary transmit line terminal panel schematic (F ) 5-50 Unit 12, tributary receive line terminal panel schematic (F ) 5-51 Unit 12, FST modem (RTY) power distribution schematic (F ) 5-52 Unit 13, connection matrix (RMC) schematic and interconnection diagram (F ) (8 sheets) 5-53 Unit 13, connection matrix (RMC) power distribution schematic (D ) 5-54 Unit 25, maintenance test mobile cabinet, power distribution schematic (C ) xvi

16 LIST OF ILLUSTRATIONS TM /1 PART FIVE Frontispiece Frontispiece Frontispiece DC Duplexed Power System Model PS1062A,, ltt-fl PN G1, Three-Quarter View (Sheet 1 of 3 sheets) DC Duplexed Power System, Model PS1063A, ITT-FL PN G2, Three-Quarter View (Sheet 2 of 3 sheets) DC Duplexed Power System, Model PS1085A, ITT-FL PN G3, Three-Quarter View (Sheet 3 of 3 sheets) Figure Title Page 1-1 DC Duplexed Power System, Model PS1062A, Front View DC Duplexed Power System, Model PS1 062A, Rear View DC Duplexed Power System, Model PS1 063A, Front View DC Duplexed Power System, Model PS1063A, Rear View DC Duplexed Power System, Model PSI085A, Front View DC Duplexed Power System, Model PS1 085A, Rear View DC Duplexed Power System, Rear Access Panels Installed DC Duplexed Power System, External Power Source Input Connections Block Diagram for DC Duplexed Power System Three-Phase Bridge Rectifier Circuit DC Duplexed Power System Alarm Panel, Model PS1062A, Front View DC Duplexed Power System Alarm Panel, Model PS1085A, Front View DC Duplexed Power System Meter Panel, Model PS1062A, Front View DC Duplexed Power System Meter Panel, Model PS1063A, Front View DC Duplexed Power System Meter Panel, Model PS1085A, Front View DC Duplexed Power System Control Chassis Assembly, Unit 23, Model PS1063A, Front View DC Duplexed Power System Control Chassis Assembly Unit 24, Model ps1063a, Front View DC Duplexed Power System Control Chassis Assembly Model PS1085A, Front View xvii

17 LIST OF ILLUSTRATIONS, (CONT'D) PART FIVE (cont) Figure Title Page 4-9 DC Duplexed Power System Regulator Drawer, Typical, Front View DC Duplexed Power System Control Chassis Assembly, Unit 23, Model PS1062A, Rear View DC Duplexed Power System Control Chassis Assembly, Unit 24, Model PS1062A, Rear View DC Duplexed Power System Control Chassis Assembly, Unit 23, Model PS1063A, Rear View DC Duplexed Power System Control Chassis Assembly, Unit 24, Model PS1063A, Rear View DC Duplexed Power System Control Chassis Assembly, Model PS1085A, Rear View DC Duplexed Power System Drawer No. 2, Model PS1062A, Top View DC Duplexed Power System Drawer No. 2, Model PS1062A, Bottom View DC Duplexed Power System Drawer No. 2, Model PS1062A, Rear View DC Duplexed Power System Drawer No. 5, Model PS1063A, Top View DC Duplexed Power System Drawer No. 5, Model PS1063A, Bottom View DC Duplexed Power System Fan Drawer, Model PS1062A, Top View DC Duplexed Power System Fan Drawer, Model PS1085A, Top View DC Duplexed Power System Printed Circuit Board, Control Chassis Assembly, Typical DC Duplexed Power System Printed Circuit Board, Fan Drawer, Typical Typical Installation of Stud-Mounted Semiconductor Devices DC Duplexed Power System Meter Panel, Model PS1085A, Rear View DC Duplexed Power System Alarm Panel, Model PS1085A, Rear View DC Duplexed Power System Printed Circuit Board Tester xviii

18 LIST OF TABLES PART FIVE Figure Title Page 1-1 Loading Particulars Operating Specifications, DC Duplexed Power System, Model PS1062A Operating Specifications, DC Duplexed Power System, Model PS1063A Operating Specifications, DC Duplexed Power System, Model PS1085A Load and Remote Sense Connection: in Unit 23, DC Duplexed Power System, Model PS1062A Load and Remote Sense Connections in Unit 24, DC Duplexed Power System, Model PS 1062A Load and Remote. Sense Connections in Unit 23, DC Duplexed Power System, Model PS 1063A Load and Remote Sense Connections in Unit 24, DC Duplexed Power System, Model PS1063A Load and Remote Sense Connections in DC Duplexed Power System, Model PS1085A Remote Alarm Indication Connections in Units 24, DC Duplexed Power Systems, Models PS1062A and PS1063A Remote Alarm Indication Connections in DC Duplexed Power System, Model PS1085A DC Duplexed Power System Operator Controls Overvoltage & Output Voltage Adjustment, DC Duplexed Power System, Model PS1062A Overvoltage & Output Voltage Adjustment, DC Duplexed Power System, Model PS1063A Overvoltage & Output Voltage Adjustment, DC Duplexed Power System, Model PS1085A Standard and System-Peculiar Test Equipment and Facilities Schematics used In all three DC Duplexed Power Systems Schematics used in DC Duplexed Power System, Model PS1062A Schematics used in DC Duplexed Power System, Model PS1063A Schematics used In DC Duplexed Power System, Model PS1085A Miscellaneous Schematics required for Testing xix

19 CHAPTER 1 INTRODUCTION AND DESCRIPTION SECTION I. GENERAL 1-1. Scope of Manual This manual provides information pertaining to the installation, operation and maintenance of the Console Remote Equipment (CRE) of the ET-A Console System. The organization and level of the manual are described in the preface which appears at the front of each bound part Purpose and Use a. CRE's are located along the main lines of the ET-A and EMT communications networks, and act as distribution links between tributary terminal sets and the rest of the system. The functions of the CRE are automatic, and are controlled by the Console Local Equipments (CLE), and by signals from the tributaries assigned to each CRE. b. Each CRE may service up to 24 tributary terminal sets. (1) At ET-A sites, the CRE services three sectors of up to eight tributaries each. Each sector is assigned two audio channels so that the tributaries assigned to that sector may be connected to either of two conferences. (2) At EMT sites, the CRE may service up to 24 individual tributaries. c. The CRE receives commands from the CLE in control of the system, decodes the messages, performs connect and disconnect operations pertaining to its tributaries, and routes other instructions to the tributaries affected. In addition, each CRE receives status data from its tributaries, inserts this data into a message format, and routes it into the system and to the CLE for status display. d. Five four-wire trunks are routed through the CRE from the ET-A communication system. These trunks are bridged in each CRE to access the CRE to the mainline without interrupting service. One trunk is used as a supervisory circuit for command and status signaling, and the other four are used as conference trunks. One of the four conference trunks, designated as a ready circuit, is constantly checked out. The ready circuit is then used to establish the next conference, and the next trunk in order becomes the ready circuit. Any conference to be initiated must be assigned on the ready circuit. 1-1

20 SECTION II. DESCRIPTION AND LEADING PARTICULARS 1-3. General Description a. The Console Remote Equipment (CRE) is housed in a single modified M-348A2 van (fig. 1-1). Figure 5-1 illustrates the position of the units comprising the CRE together with the physical characteristics of the van. Four elevation (vertical) views are included which depict the appearance of the equipment as viewed from four different points within the van. b. Three identical air conditioners (units 28, 29 and 30; fig. 5-1, items 18) are included in the van, and provide cooling or heating as required, to maintain favorable temperature conditions. The forced air is routed through three air ducts (fig. 5-1, item 19) which terminate above units 12, 23, and 24 (fig. 5-1, items 10, 13 and 14, respectively), directing the air out into the central area of the van. Dual intake fans (fig. 5-1, item 21) are provided for ventilating the van when the air conditioners are not in use. c. Four primary ac power cables from external generators are brought into the van by means of a connector panel (fig. 5-1, item 16). The power is then routed through line filters to four circuit breaker and distribution boxes. Signal cables to/from external MUX equipment are connected to the van at a signal distribution panel in the van wall. This panel, in turn, feeds the distribution frame (fig. 5-1, item 15) inside the van. Signal and power cables interconnecting the units within the van are run just beneath the ceiling on overhead cable trays (fig. 5-1, item 20) and along portions of the frame. d. All major units in the CRE are given unit numbers, as shown in figure 5-1. The van itself, including the signal distribution frame, is designated unit 1. Note that there are no units designated 2, 3, or 14 through 22. The remaining units are discussed in the following paragraphs Logic Equipment a. The logic equipment is housed in cabinets or bays designated units 4 through 9 (fig. 5-1, items 2 through 7). The logic circuits in these units are fabricated on plug-in printed-circuit cards which can be inserted and removed from the front of the cabinets. A typical logic card is shown in figure 1-2. Each card is approximately four by six inches in size and contains an ejector handle riveted to the front end of the card to aid in removing and inserting the card. To unplug and remove a card, the bottom of the handle is pushed upward. The handles are color coded white and red, corresponding to colored strips above the slots in which the cards are mounted to prevent damage that might occur if a card were inserted into wrong slot. Each card contains test point jacks, numbered J1 through J14, mounted near the forward edge of the card so that readings can be taken under operating conditions while the card is electrically connected to its associated circuits. The plug connector for each card is fastened to its rear edge. The cards are mounted in individual nylon slots; there are 27 slots to a row, two rows (54 slots) to a nest, and six nests (324 slots) to a cabinet. 1-2

21 Figure 1-1. Console remote equipment van. 1-3

22 Figure 1-2. Typical logic card. 1-4

23 b. A typical logic cabinet or bay, illustrated in figure 1-3, is approximately 20 inches wide, 62 inches high, and seven inches deep, and can house up to 324 logic cards. The bay houses six logic card nests designated A2 through A7. Each nest, housing up to 54 logic cards, is approximately 10 inches high, 19 inches wide, and eight inches deep. The nests are mounted in standard 59-inch rack panels. The slot position, color code, and type number identifying each card in a nest are printed on the black panel strips that separate the nests. The rear of each nest contains the 33-pin connectors into which the logic cards are plugged. c. Each logic bay contains LOGIC FAULT and POWER FAULT indicators located on a narrow panel at the top front of the cabinet. The LOGIC FAULT indicator lights red whenever an error is disclosed by fault detection circuits within the logic cabinet. The POWER FAULT indicator lights red when an overload exists on any of the dc input lines to the bay. d. Level Al of each logic bay contains the dc circuit breakers for that bay. These breakers open in the event of an overload on any of the dc lines. e. Each bay can be swung out from the main supporting structure to expose the nest wiring and the signal cables (fig. 1-4). A mechanical stop prevents the bay from opening too far, and a locking mechanism keeps the bay from moving once it is open. The signal connector panel is at the top rear of the bay. A dc power bus, with taps for each logic card row, runs vertically along the right side of each cabinet, as viewed from the rear. A 1-volt ac transformer and associated receptacle are mounted on the supporting frame in back of each logic bay. These transformers provide filament voltage for the indicator lamps used on some of the logic cards. f. Figure 1-5 illustrates unit 4 which contains the remote command receive (RCR) circuits. These circuits receive, decode, monitor, and temporarily store the supervisory command messages sent from the Console Local Equipment (CLE). Level A2/A3 contains three diode patch fields used to establish tributary and preset conference addresses together with the tributary preset conference assignments. Level A4 contains RCR patchfield circuitry, and levels A5 and A6 contain RCR receive, decode, and storage circuitry. Level A7 is blank. 1-5

24 g. Figure 1-6 shows a typical tributary control cabinet. There are three identical cabinets, units 5, 6, and 7, each containing the remote tributary group (RTG) and remote tributary single (RTS) logic functions for one sector of up to eight tributaries. One RTG circuit is common to a group of eight tributaries while each RTS circuit services one tributary. The function of the RTG and RTS circuits is to assemble and send digital command information to the proper tributaries. These circuits also receive and process digital status information from their respective tributaries. Levels A2 and A3 of each tributary control cabinet house the RTG circuitry for a particular sector, and levels A4 through A7 contain the RTS circuitry for that sector. The RTS circuits are packaged one row of logic cards per tributary. Level A8, located at the rear of each cabinet, is a terminal board which permits disabling alarm circuits associated with unused RTS circuits. h. Figure 1-7 shows the trunk matrix control cabinet, unit 8, which contains the trunk matrix control (TMC) and the remote tributary common (RTC) logic circuits. The TMC circuits control the operation of the trunk matrix which makes audio connections between system trunk lines and remote site supervisory, ready, and conference circuits. The RTC circuit is common to the three remote tributary group (RTG) and the 24 remote tributary single (RTS) circuits located in units 5, 6, and 7. The RTC circuit processes digital status information from the tributary sites for transmission to the Console Local Equipment (CLE) sites. Levels A2 and A3 of unit 8 contain the TMC circuitry; levels A4, A5, and A7 are blank; and level A6 contains the RTC circuitry. i. The select matrix control cabinet, unit 9, shown in figure 1-8, contains three identical select matrix control (SMC) circuits, one for each sector. The SMC circuits control the operation of the select matrix, which makes the audio connections between the CRE conference circuits and the tributary equipment. Levels A2 and A3 contain the group 1 (sector 1) SMC circuits, levels A4 and A5 contain the group 2 SMC circuits, and levels A6 and A7 house the group 3 SMC circuits. Levels A8, A10, and A12, for groups 1, 2, and 3, respectively, are located at the rear of the cabinet; these levels consist of terminal boards which permit tributaries to be connected on a part line or an individual basis. The terminal boards also permit the alarm circuits associated with unused groups of tributaries to be disabled. Levels A9 and All at the rear of unit 9 are not used. 1-6